A federal judge decided Tuesday to keep records related to the controversial Boston College Belfast Project case under seal, saying they relate to an ongoing criminal investigation in Northern Ireland.

The decision was, in part, a response to a request by NBC News to unseal transcripts of the controversial project, which has made international headlines.

The request had been opposed by researchers involved in the BC project.

Young ordered BC in 2011 to turn over certain interviews collected under the Belfast Project, an academic project on the Troubles, the decades-long conflict between those who would unite Northern Ireland with the Republic of Ireland and those who want it to remain within the United Kingdom.

The US government sought the interviews on behalf of the United Kingdom, which continues to investigate crimes committed at the time of the Troubles, including the murder of Jean McConville, whom the Irish Republican Army suspected of being an informant.

Some of the interviews were with former members of the IRA, who agreed to speak to the journalists under the condition of anonymity, under an agreement that the interviews not be released until after they died.

US Department of Justice officials had also opposed the unsealing of certain records, such as affidavits and characterizations of the investigation, saying the investigation is ongoing. Police in Northern Ireland arrested Sinn Fein leader Gerry Adams last month for questioning in connection with the killing of McConville. He was released and has denied being involved.

“It is critical to the United States that we be able to work with our partners abroad, that we can obtain information for them without compromising the integrity of an investigation,” said John McNeil, first assistant US attorney in Massachusetts. “There is an ongoing investigation in the United Kingdom, and the United Kingdom has asked us to maintain the integrity of that investigation.”